1. Field of the Invention
The present invention relates to outdoor fish aquariums.
2. Description of the Prior Art
Artificial ponds for aquatic life provide various features to provide a favorable man-made environment for the aquatic life placed in the pond.
U.S. Pat. No. 4,972,801 issued Nov. 27, 1990 to Robert D. Hunt discloses a pumping system for producing oxygen enriched water for aquatic life.
U.S. Pat. No. 4,892,651 issued on Jan. 9, 1990 to Theodore L. Hill discloses a filtering system for fish ponds.
U.S. Pat. No. 4,306,394 issued on Dec. 22, 1981 to Stanley R. Blakeway discloses swimming pools of various designs.
The Encon International Fiberglass article discloses various spas of different design made of fiberglass.
None of the prior art as cited above disclose varying the depth of an outdoor fish aquarium to prevent fish from freezing.